#include<iostream>
#include<vector>
#include<string>
using namespace std;

class FoldPaper {
private:
    vector<string> ret;
public:
    vector<string> foldPaper(int n) {
        this->process(1,n,true);
        return ret;
    }

    void process(int i,int n,bool down)
    {
        if(i > n){
            return;
        }
        this->process(i+1,n,true);
        string cur = down ? "down" : "up";
        // cout << cur << " ";
        ret.push_back(cur);
        this->process(i+1,n,false);
    }
};

int main(){
    FoldPaper().foldPaper(3);
    return 0;
}